In a forest in western Poland lies an abandoned Soviet nuclear base called “Special object 3003 Templewo”. On this base, in the shade of pines and spruces slowly engulfing it, lies a flat-topped bunker that once stored warheads. Inside it is a black pit into which ants fall but never return.

You can’t see the pit, though. It’s covered by an enormous wood ant nest some 15 feet across and 2 feet high. For reasons that must remain known only to the ants, they chose to site it over a 16-foot long ventilation shaft leading to the bunker. The cover rusted long ago, and when an unfortunate ant passes over this peril, it drops to its doom. But it’s not alone. Not by far.

In the summer, the ants climb the walls. These escape efforts are doomed, however, by the fact that upon reaching the ceiling, they cannot cling to it; the scientists never observed them walking on it. Though the entrance to the ventilation shaft lies a few tantalizing feet away from the top of the wall, it might as well be a million miles.

They have no light, little water, nowhere near enough food, and the temperature never exceeds 10°C(50°F). Turning the lights on (as when entomologists or bat-counters creep inside) does not improve matters. Flaking paint hangs from the walls like skin peeling from a sun burn, while dirt, rubble, and trash cover the terracotta floor.

Inside their bunker, the ants have built a home and carried on as if nothing is amiss. Most of the floor is covered by the nest, a dirt mound 10 inches high with many openings. They tend their home just as if they were on the surface, carefully sculpting it, cleaning it, and making sure the entrances remain clear. They carry their dead to cemeteries strewn about the exposed floors and flat surfaces of the nest. The nest has little of the building materials typically used by wood ants, but they have made do with what they have.

Yet as hard as the ants work, they work in vain. Neither in the vast ant cemeteries nor inside the mound, once excavated by scientists, were any sign of ant larvae found. It’s probably way too cold for reproduction, even if a queen did fall in, because the lack of food makes it impossible for the workers to regulate the temperature of the mound. There’s nowhere near enough food for this energy-intensive activity.

The ants aren’t completely alone in the bunker. Roosting bats drop a meager supply of guano. The bodies of other insects likely caught by the workers of the colony in the forest above stud the cemetery. And living mites of species normally found in decaying plant material are present in great quantities (probably feeding off the ant cemeteries), along with ant-loving spiders and beetles. Although these creatures could theoretically serve as ant chow, they are not either big enough or numerous enough to serve as sufficient food for all the ants.

Without a queen, without offspring, and without sufficient food or warmth, how can such a city persist? The grim truth is that though many die, they are quickly replaced by the inexorable rain of ants from the ceiling. The corpses in the cemeteries lie several centimeters thick. By measuring the density of bodies in these cemeteries along with their volume, the scientists calculated that the number of the dearly departed in the bunker totals some two million. And today the live population maintaining this shadow nest is in the hundreds of thousands, perhaps near a million.

Ants are famously one of the most successful organisms on the planet, and are certainly numerically and in biomass the dominant insect. Enterprising and relentless, they are found virtually everywhere on Earth. Yet even E. O. Wilson noted back in the early 1960s that there is one habitat that ants are unlikely ever to colonize en masse: caves, especially deep caves. There’s just not enough food to support the quorum necessary for even a basic colony, except in places like the tropics or Mediterranean where temperatures are mild and the bat guano free flowing. Yet there are precedents for ant colonies in extremis.

In an experiment that would surely never be replicated today performed on islands in the Gulf of Finland, wood ant colonies found only on large forested islands were introduced to smaller islands lacking wood ants to see how little they could scrape by on. Incredibly, a colony managed to survive almost 30 years on a barren “islet” less than 0.2 hectares in size whose only food source was the honeydew produced by the aphids on the islet’s lone pine.

Ants have also shown themselves more than willing before to consider "alternative" housing arrangements when conditions warrant. That can include such surprising choices as the inside of large mushrooms like the tasty Sparassis crispa and the poisonous but gloriously lurid false morel Gyromitra esculenta. According to the authors of this paper, one ant colony, surely not the only one, even nested in the chassis of an abandoned car (sadly, make and model unknown), ultimately reaching the interior. They built their nest from bits of mud and plants stuck to the bottom of the car.

But, as the authors of the paper point out, these ants chose their homes. The ants in the nuclear weapons bunker had no choice. Or rather, when faced with a choice to give up and die or carry on, they chose to carry on.

For a human, it would be a grim, depressing, Count-of-Monte-Cristo-like existence, and it is hard not to contemplate them without pity. But these ants carry resolutely on, partly because they are programmed to, partly because they do not understand there is no escape, and partly because, hey, what else are you going to do? To the extent any organism gains satisfaction from carrying out its purpose in life, how can we say these ants are unhappy or suffering? If I were marooned on Mars with no hope of rescue and little food, I hope I too would carry on like Matt Damon in The Martian. It’s a heck of a lot less boring than sitting around waiting to die.

ABOUT THE AUTHOR(S)

Jennifer Frazer

Jennifer Frazer is a AAAS Science Journalism Award-winning science writer. She has degrees in biology, plant pathology/mycology, and science writing, and has spent many happy hours studying life in situ.

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